Prevalence and Disease Spectrum of Extracoronary Arterial Abnormalities in Spontaneous Coronary Artery Dissection

The comprehensive care of the post-SCAD patient

Spontaneous coronary artery dissection (SCAD) is the nonatherosclerotic, nontraumatic dissection of an epicardial coronary artery which is predominantly caused by intramural hematoma formation or intimal disruption. SCAD is an increasingly recognized cause of acute coronary syndrome (ACS) in young women and its true prevalence may be underestimated due to its underdiagnosis. The pathogenesis of SCAD is multifaceted and influenced by gender-specific factors, hormonal fluctuations, genetics, arteriopathies, and physical and emotional stressors. Although the pathogenesis of SCAD is multifaceted, current guidance on the care of the post-SCAD patient is limited. Moreover, it is necessary to address each of the different components contributing to the pathogenesis of SCAD in order to improve outcomes and quality of life in this patient population. This literature review aims to consolidate the current knowledge on the medical management, rehabilitation, reproductive and mental health care, and comorbidities that affect SCAD survivors.

Spontaneous coronary artery dissection in the context of tamoxifen; Is there any correlation?

Key Clinical Message

Clinicians should consider spontaneous coronary artery dissection in middle-aged women presenting with acute coronary syndromes and a history of tamoxifen use, to ensure timely diagnosis, and appropriate management strategies.

Abstract

Spontaneous coronary artery dissection (SCAD) is characterized by a non-iatrogenic, nontraumatic separation of the coronary artery wall, contributing to acute coronary syndromes (ACS), and sudden cardiac death. SCAD predominantly affects the left anterior descending artery (LAD) and is frequently observed in middle-aged women. This condition has been associated with cancer treatment and exogenous hormones exposure. The diagnostic gold standard remains coronary angiography, management strategies include conservative measures, percutaneous coronary intervention (PCI), and coronary artery bypass graft surgery (CABG). We describe a case of a 54-year-old woman with breast cancer and a history of tamoxifen use, presenting with SCAD in the posterolateral branch (PLB) originating from the left circumflex artery (LCX), and right coronary artery (RCA) and managed conservatively.

From Atherosclerosis to Spontaneous Coronary Artery Dissection: Defining a Clinical and Genetic Risk Spectrum for Myocardial Infarction

PURPOSE OF REVIEW

Spontaneous coronary artery dissection (SCAD) has been increasingly recognized as a significant cause of acute myocardial infarction (AMI) in young and middle-aged women and arises through mechanisms independent of atherosclerosis. SCAD has a multifactorial etiology that includes environmental, individual, and genetic factors distinct from those typically associated with coronary artery disease. Here, we summarize the current understanding of the genetic factors contributing to the development of SCAD and highlight those factors which differentiate SCAD from atherosclerotic coronary artery disease.

RECENT FINDINGS

Recent studies have revealed several associated variants with varying effect sizes for SCAD, giving rise to a complex genetic architecture. Associated genes highlight an important role for arterial cells and their extracellular matrix in the pathogenesis of SCAD, as well as notable genetic overlap between SCAD and other systemic arteriopathies such as fibromuscular dysplasia and vascular connective tissue diseases. Further investigation of individual variants (including in the associated gene PHACTR1) along with polygenic score analysis have demonstrated an inverse genetic relationship between SCAD and atherosclerosis as distinct causes of AMI. SCAD represents an increasingly recognized cause of AMI with opposing clinical and genetic risk factors from that of AMI due to atherosclerosis, and it is often associated with complex underlying genetic conditions. Genetic study of SCAD on a larger scale and with more diverse cohorts will not only further our evolving understanding of a newly defined genetic spectrum for AMI, but it will also inform the clinical utility of integrating genetic testing in AMI prevention and management moving forward.

Tortuosity in non-atherosclerotic vascular diseases is associated with age, arterial aneurysms, and hypertension

BACKGROUND

Increased arterial tortuosity has been associated with various cardiovascular complications. However, the extent and role of arterial tortuosity in non-atherosclerotic vascular diseases remain to be fully elucidated. This study aimed to assess arterial tortuosity index (ATI) in patients with non-atherosclerotic vascular diseases and the associated factors.

METHODS

This is a retrospective analysis of patients with non-atherosclerotic vascular diseases referred to the Malformation and Rare Vascular Disease Center at the University Hospital in Lausanne (Switzerland). Computed tomography angiography (CTA) images performed between October 2010 and April 2022 were retrieved and the aortic tortuosity index (ATI) was calculated. Patients were classified based on diagnosis into the following groups: arterial dissection & aneurysm, arteritis & autoimmune disease, hereditary connective tissue diseases, and fibromuscular dysplasia (FMD). Univariate and multivariate logistic regression analysis was used to determine potentially relevant predictors of aortic tortuosity.

RESULTS

The mean age upon computed tomography angiography (CTA) was 46.8 (standard deviation [SD] 14.6) years and 59.1% of the patients were female. Mean ATI was higher in patients over 60 years old (1.27), in those with arterial aneurysms (mean: 1.11), and in those diagnosed with hypertension (mean: 1.13). When only patients over 60 years old were considered, those diagnosed with connective tissue diseases had the highest ATI. At multivariate regression analysis, increasing age (p < 0.05), presence of arterial aneurysms (p < 0.05), and hypertension (p < 0.05) were independently associated with ATI.

CONCLUSIONS

The ATI may be a promising tool in diagnostic evaluation, cardiovascular risk stratification, medical or surgical management, and prognostic assessment in several non-atherosclerotic vascular conditions. Further studies with longitudinal design and larger cohorts are needed to validate the role of ATI in the full spectrum of vascular diseases.

Spontaneous coronary artery dissection: review, case report and analysis of COVID-19-related cases

Spontaneous coronary artery dissection (SCAD) accounts for 1-4% of all acute coronary syndromes (ACS). Since the first description in 1931, our understanding of the disease has evolved; however, its pathophysiology and management are still a matter of debate. SCAD typically occurs in a middle-aged woman with no or few traditional cardiovascular risk factors. Two hypotheses have been proposed to explain the pathophysiology depending on the primary event: an intimal tear in the "inside-out" hypothesis and a spontaneous hemorrhage from the vasa vasorum in the "outside-in" hypothesis. Etiology appears to be multifactorial: different predisposing and precipitating factors have been identified. Coronary angiography is the gold standard for the diagnosis of SCAD. Current recommendations on the treatment of SCAD patients are based on expert opinions: a conservative strategy is preferred in hemodynamically stable SCAD patients, while urgent revascularization should be considered in hemodynamically unstable patients. Eleven cases of SCAD in COVID-19 patients have already been described: although the exact pathophysiological mechanism remains unclear, COVID-19-related SCAD is considered a combination of significant systemic inflammatory response and localized vascular inflammation. We present a literature review of SCAD, and we report an unpublished case of SCAD in a COVID-19 patient.

Concurrent spontaneous coronary dissection and reversible cerebral vasoconstriction syndrome during postnatal care

BACKGROUND

Pregnancy-associated spontaneous coronary artery dissection (SCAD) and reversible cerebral vasoconstriction syndrome (RCVS) are rare conditions that may occur during pregnancy and the postpartum period. The coexistence of both diseases may pose a risk to patients, potentially resulting in a variety of complications and clinical manifestations. This is considered the first case of a patient who successfully recovered from a critical condition in the postpartum period, with contemporaneous SCAD and RCVS.

CASE PRESENTATION

A 33-year-old female with no known medical history was referred to the emergency department after experiencing cardiac arrest, which occurred 1 week after giving birth to her third child. She complained of sudden anterior squeezing chest pain, accompanied by a headache, and eventually collapsed due to ventricular fibrillation with seizure. She was successfully resuscitated after receiving basic life support. She showed an alert mentality and did not experience any further seizure events or additional neurological symptoms. Although vital sign remained stable, the level of highly sensitive troponin I was significantly elevated. Electrocardiography revealed sinus rhythm with T-wave inversion at V1-4, while chest computed tomography (CT) demonstrated severe aspiration pneumonia. The patient was admitted to the intensive care unit due to a high requirement of O2 supply. A consultation with the neurologic department and a brain magnetic resonance angiography (MRA) were conducted for the thunderclap headache. The brain MRA demonstrated stenosis in the basilar artery, the right M2 segment, and bilateral A1 segments, along with sulcal hyperintensity on post-contrast fluid-attenuated inversion recovery (FLAIR) suggesting blood-brain barrier breakdown due to vasoconstriction. Formal echocardiography showed regional wall motion abnormality in the left anterior descending artery (LAD) territory. After the improvement of pneumonia, a coronary angiography was performed, revealing diffuse luminal narrowing from the mid to distal LAD due to a long segmental, extensive dissection. We decided to maintain the medical therapy. A follow-up coronary CT angiography performed 6 months later revealed complete remission of the dissected coronary vessel, and a brain MRA checked 3 months later showed resolved vasoconstriction of the relevant cerebral vessels.

CONCLUSIONS

The physicians must be aware of pregnancy-associated complications in certain patients. Clear diagnoses and proper treatments are required in pregnant patients who may be exposed to multiple acute conditions, in order to reduce complications and achieve favorable outcomes.

Prevalence and outcomes of select rare vascular conditions in females: A descriptive review

Rare vascular conditions frequently pose a diagnostic and therapeutic dilemma for health care providers. Several of these conditions have distinct relevance to females populations but, due to their infrequency, there has been little reported on the outcomes of rare vascular conditions specifically in females populations. We performed a literature review of a selection of three rare vascular conditions known to either disproportionately affect females (median arcuate ligament syndrome and fibromuscular dysplasia) or have unique manifestations in females populations (vascular Ehlers-Danlos syndrome). We performed a descriptive review of the literature focused on these three vascular conditions and identified aspects of the current available research describing sex-based differences in prevalence, any pathophysiology explaining the observed sex-based differences, and the contribution of sex to outcomes for each disease process. In addition, considerations for pregnant females with respect to each rare vascular disease process are discussed.

Pathophysiology of spontaneous coronary artery dissection: hematoma, not thrombus

Spontaneous coronary artery dissection (SCAD) accounts for 1.7%-4% of all acute coronary syndrome presentations, particularly among young women with an emerging awareness of its importance. The demarcation of acute SCAD from coronary atherothrombosis and the proper therapeutic approach still represents a major clinical challenge. Certain arteriopathies and triggers are related to SCAD, with high variability in their prevalence, and often, the cause remains unknown. The objective of this review is to provide contemporary knowledge of the pathophysiology of SCAD and possible therapeutic solutions.

Invasive imaging modalities in a spontaneous coronary artery dissection: when "believing is seeing"

Spontaneous coronary artery dissection (SCAD) is a rare but increasingly recognized cause of acute coronary syndrome (ACS) with recent advancements in cardiac imaging facilitating its identification. However, SCAD is still often misdiagnosed due to the absence of angiographic hallmarks in a significant number of cases, highlighting the importance of meticulous interpretation of angiographic findings and, when necessary, additional usage of intravascular imaging to verify changes in arterial wall integrity and identify specific pathoanatomical features associated with SCAD. Accurate diagnosis of SCAD is crucial, as the optimal management strategies for patients with SCAD differ from those with atherosclerotic coronary disease. Current treatment strategies favor a conservative approach, wherein intervention is reserved for cases with persistent ischemia, patients with high-risk coronary anatomy, or patients with hemodynamic instability. In this paper, we provide a preview of invasive imaging modalities and classical angiographic and intravascular imaging hallmarks that may facilitate proper SCAD diagnosis.

From Fibromuscular Dysplasia to Arterial Dissection and Back

Fibromuscular dysplasia (FMD) is an idiopathic and systemic non-inflammatory and non-atherosclerotic arterial disease. Fifteen to 25% of patients with FMD present with arterial dissection in at least one arterial bed. Conversely, a substantial number of patients with renal, carotid, and visceral dissection have underlying FMD. Also, while few patients with FMD develop coronary artery dissection, lesions suggestive of multifocal FMD have been reported in 30-80% of patients with spontaneous coronary artery dissection (SCAD), and the relation between these two entities remains controversial. The frequent association of FMD with arterial dissection, both in coronary and extra-coronary arteries raises a number of practical and theoretical questions: (i) Are FMD and arterial dissections two different facets of the same disease or distinct though related entities? (ii) Is SCAD just a manifestation of coronary FMD or a different disease? (iii) What is the risk and which are predictive factors of developing arterial dissection in a patient with FMD? (iv) What proportion of patients who experienced an arterial dissection have underlying FMD, and does this finding influence the risk of subsequent arterial complications? In this review we will address these different questions using fragmentary, mostly cross-sectional evidence derived from large registries and studies from Europe and the United States, as well as arguments derived from demographics, clinical presentation, imaging, and when available histology and genetics. From there we will derive practical consequences for nosology, screening and follow-up.

Fibromuscular dysplasia of the brachial artery in patients with spontaneous coronary artery dissection: a case series and literature review

Spontaneous coronary artery dissection (SCAD) is diagnosed in a very small percentage of patients with suspected acute coronary syndromes who undergo emergency coronary angiography. Although fibromuscular dysplasia (FMD) is known to coexist in patients with SCAD, the vascular sites of FMD and their frequency have not yet been clarified. We retrospectively reviewed the medical records of 16 patients who were diagnosed with and treated for SCAD at our hospital between 1 January 2011 and 31 January 2023. We have summarized their baseline and clinical characteristics and medical variables, including coronary and upper extremity angiography and in-hospital outcomes. One of our patients had concurrent cardiac tamponade requiring pericardial drainage, and another went into hemorrhage shock the following day from dissection of the gastric retroperitoneal artery. Characteristic angiographic features of partial or diffuse nonatherosclerotic stenosis were observed mainly in the distal parts of the coronary arteries or their branches. Notably, in six patients with SCAD who underwent upper extremity angiography, FMD of the brachial artery was revealed. For the first time, to our knowledge, we found a high prevalence of multifocal FMD of the brachial artery in patients with SCAD.

Assessment of extra-coronary peripheral arteriopathy in spontaneous coronary dissection: state of the art in non-invasive imaging techniques and future perspectives

Spontaneous coronary artery dissection (SCAD) has been recognized as an important cause of acute coronary syndrome in women ≤ 50 years old, and up to 43% of pregnancy-associated myocardial infarction. SCAD has a strong association with extra-coronary arteriopathies, including either more common entities such as dissections, intracranial or other aneurysms, and extra-coronary and coronary arterial tortuosity or less common inherited vascular disorders such as Ehlers-Danlos syndrome, Marfan syndrome, and Loeys-Dietz syndrome, leading to the conclusion that systemic arterial disorders may underlie SCAD. Fibromuscular dysplasia is the most common extra-coronary vascular abnormality identified among these patients, also sharing a common genetic variant with SCAD. The American Heart Association, in a scientific statement regarding the management of SCAD, recommends that patients with SCAD should undergo additional evaluation with imaging techniques including either computed tomography angiography (CTA) or magnetic resonance angiography (MRA). MRA has been shown to have sufficient diagnostic accuracy in identifying extra-coronary arterial abnormalities, almost equal to CTA and conventional angiography. The aim of this review is to appraise the most recent important evidence of extra-coronary arteriopathy in the setting of SCAD and to discuss the strengths and weaknesses of various non-invasive imaging methods for screening of extra-coronary arteriopathies in patients with SCAD.

Genome-wide association meta-analysis of spontaneous coronary artery dissection identifies risk variants and genes related to artery integrity and tissue-mediated coagulation

Spontaneous coronary artery dissection (SCAD) is an understudied cause of myocardial infarction primarily affecting women. It is not known to what extent SCAD is genetically distinct from other cardiovascular diseases, including atherosclerotic coronary artery disease (CAD). Here we present a genome-wide association meta-analysis (1,917 cases and 9,292 controls) identifying 16 risk loci for SCAD. Integrative functional annotations prioritized genes that are likely to be regulated in vascular smooth muscle cells and artery fibroblasts and implicated in extracellular matrix biology. One locus containing the tissue factor gene F3, which is involved in blood coagulation cascade initiation, appears to be specific for SCAD risk. Several associated variants have diametrically opposite associations with CAD, suggesting that shared biological processes contribute to both diseases, but through different mechanisms. We also infer a causal role for high blood pressure in SCAD. Our findings provide novel pathophysiological insights involving arterial integrity and tissue-mediated coagulation in SCAD and set the stage for future specific therapeutics and preventions.

Spontaneous coronary artery dissection: the emerging role of coronary computed tomography

Spontaneous coronary artery dissection (SCAD) is a cause of acute coronary syndrome and myocardial infarction, more frequent among young women. Invasive coronary angiography (ICA) is the gold standard for the diagnosis of SCAD, although the risk of propagating dissection flap is considerable. Therefore, coronary computed tomography angiography (CCTA) is an emerging alternative modality to diagnose SCAD with the advantage of being a non-invasive technique. Clinicians should be aware of the predisposing conditions and pathophysiology to raise the pre-test probability of SCAD and select the most appropriate diagnostic tools. In recent times, improvements in spatial and temporal resolution and the use of semi-automated software providing quantitative assessment make CCTA a valid alternative to ICA also for the follow-up. Moreover, CCTA may be helpful to screen and evaluate extra-coronary arteriopathies closely related to SCAD. In this review, we illustrate the current and the potential role of CCTA in the diagnosis of SCAD, highlighting advantages and disadvantages of this imaging modality compared to ICA.

Multivessel spontaneous coronary artery dissection: Clinical features, angiographic findings, management, and outcomes

BACKGROUND

Spontaneous coronary artery dissection (SCAD) is a rare cause of acute coronary syndrome. Multivessel (MV) SCAD is a challenging clinical presentation that might be associated to a worse prognosis compared with patients with single-vessel (SV) involvement.

METHODS

The Spanish multicentre nationwide prospective SCAD registry included 389 consecutive patients. Patients were classified, according to the number of affected vessels, in SV or MV SCAD. Major adverse events (MAE) were analyzed during hospital stay and major cardiac or cerebrovascular adverse events (MACCE) at long-term clinical follow-up.

RESULTS

A total of 41 patients (10.5%) presented MV SCAD. These patients had more frequently a previous history of hypothyroidism (22% vs 11%, p = 0.04) and anxiety disorder (32% vs 16%, p = 0.01). MV SCAD patients presented more often as non-ST segment elevation myocardial infarction (73% vs 52%, p = 0.01) and showed less frequently type 1 angiographic lesions (12% vs 21%, p = 0.04). An impaired initial Thrombolysis In Myocardial Infarction (TIMI) flow 0-1 was less frequent (14% vs 29%, p < 0.01) in MV SCAD. In both groups, most patients were treated conservatively (71% vs 79%, p = NS). No differences were found regarding in-hospital MAE or MACCE at late follow-up (median 29 ± 11 months). However, the rate of stroke was higher in MV SCAD patients, both in-hospital (2.4% vs 0%, p < 0.01) and at follow-up (5.1% vs 0.6%, p = 0.01).

CONCLUSIONS

Patients with MV SCAD have some distinctive clinical and angiographic features. Although composite clinical outcomes, in-hospital and at long-term follow-up, were similar to those seen in patients with SV SCAD, stroke rate was significantly higher in patients with MV SCAD.

Coronary fibromuscular dysplasia with three-vessel involvement: a rare cause of ischaemic dilated cardiomyopathy in a very young male

Coronary artery disease of non-atherosclerotic aetiology, while rare in incidence, can have a wide aetiology, such as fibromuscular dysplasia, which is a non-inflammatory arteriopathy of numerous histopathological types of fibromuscular tissue accumulation. This brief report describes the case of a 22-year-old male with a recently developed dilated cardiomyopathy and a history of aborted cardiac arrest at the age of 14 years. Coronary angiogram revealed severe three vessels disease, while optical coherence tomography established fibromuscular dysplasia as aetiology. Balloon and stent angioplasty was performed guided by fractional flow reserve with acceptable angiographic result.

Individualized exercise prescription and cardiac rehabilitation following a spontaneous coronary artery dissection or aortic dissection

Aims

Prescribed aerobic-based exercise training is a low-risk fundamental component of cardiac rehabilitation (CR). Secondary prevention therapeutic strategies following a spontaneous coronary artery dissection (SCAD) or aortic dissection (AD) should include CR. Current exercise guidance for post-dissection patients recommends fundamental training components including target heart rate zones are not warranted. Omitting fundamental elements from exercise prescriptions risks safety and makes it challenging for both clinicians and patients to understand and implement recommendations in real-world practice. We review the principles of exercise prescription for CR, focusing on translating guidelines and evidence from well-studied high-risk CR populations to support the recommendation that exercise testing and individualized exercise prescription are important for patients following a dissection.

Methods and results

When patients self-perceive exercise intensity there is a tendency to underestimate intensities within metabolic domains that should be strictly avoided during routine exercise training following a dissection. However, exercise testing associated with CR enrolment has gained support and has not been linked to adverse events in optimally medicated post-dissection patients. Graded heart rate and blood pressure responses recorded throughout exercise testing provide key information for developing an exercise prescription. An exercise prescription that is reflective of medical history, medications, and cardiorespiratory fitness optimizes patient safety and yields improvements in blood pressure control and cardiorespiratory fitness, among other benefits.

Conclusion

This clinical practice and education article demonstrates how to develop and manage a CR exercise prescription for post-acute dissection patients that can be safe and effective for maintaining blood pressure control and improving cardiorespiratory fitness pre-post CR.

The complex genetic basis of fibromuscular dysplasia, a systemic arteriopathy associated with multiple forms of cardiovascular disease

Artery stenosis is a common cause of hypertension and stroke and can be due to atherosclerosis accumulation in the majority of cases and in a small fraction of patients to arterial fibromuscular dysplasia (FMD). Artery stenosis due to atherosclerosis is widely studied with known risk factors (e.g. increasing age, male gender, and dyslipidemia) to influence its etiology, including genetic factors. However, the causes of noninflammatory and nonatherosclerotic stenosis in FMD are less understood. FMD occurs predominantly in early middle-age women, a fraction of the population where cardiovascular risk is different and understudied. FMD arteriopathies are often diagnosed in the context of hypertension and stroke and co-occur mainly with spontaneous coronary artery dissection, an atypical cause of acute myocardial infarction. In this review, we provide a comprehensive overview of the recent advances in the understanding of molecular origins of FMD. Data were obtained from genetic studies using complementary methodological approaches applied to familial, syndromic, and sporadic forms of this intriguing arteriopathy. Rare variation analyses point toward mechanisms related to impaired prostacyclin signaling and defaults in fibrillar collagens. The study of common variation, mainly through a recent genome-wide association study, describes a shared genetic link with blood pressure, in addition to point at potential risk genes involved in actin cytoskeleton and intracellular calcium homeostasis supporting impaired vascular contraction as a key mechanism. We conclude this review with future strategies and approaches needed to fully understand the genetic and molecular mechanisms related to FMD.